Updating Service Reference destroys most members in Reference.cs

If you update or add a service reference in Visual Studio and you don’t get all of the methods you were expecting, there was probably a silent error within the svcutil process which adds the reference.

You can check what the error is by running the command yourself. Open a Visual Studio Command Prompt, navigate to a non-admin directory (like C:/temp/) and run a command like this:

The d option is the directory to spawn code into, and can be set to anything. The r options is a referenced assembly against which you want to check common types. So for example, my service publishes types from an SG.Common.Messages project which is also referenced by the project which is trying to add the Service Reference:

Attempting to download metadata from 'http://localhost/SG/WidgetDemands/WidgetDemandsService.svc' using WS-Metadata Exchange or DISCO.
Error: Cannot import wsdl:portType
Detail: An exception was thrown while running a WSDL import extension: System.ServiceModel.Description.DataContractSerializerMessageContractImporter
Error: List of referenced types contains more than one type with data contract name 'Demand' in namespace 'http://www.stegriff.co.uk/SG/WidgetsDemands/v1.0.0.0/'.
Need to exclude all but one of the following types. Only matching types can be valid references:
"SG.Services.Common.Messages.Renewals.Demand, SG.Services.Common.Messages, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" (not matching)
"SG.Services.Common.Messages.NewBusiness.Demand, SG.Services.Common.Messages, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null" (matching)
XPath to Error Source: //wsdl:definitions[@targetNamespace='http://tempuri.org/']/wsdl:portType[@name='IPanelProductQuotationsService']

…so I can see that I have two types in the service namespace both called ‘Demand’, and that’s the error. For me, the fix was to change one of them to ‘DemandIdentifier’, but I could have rationalised that class altogether and re-used the same class for both purposes.